Constant velocity joints (CV joints) are common components in automotive vehicles. Typically constant velocity joints are used where transmission of rotating motion at a constant velocity is desired. The common types of constant velocity joints are a plunging tripod, a fixed tripod, a plunging ball joint and a fixed ball joint. These types of joints are currently used in front wheel drive vehicles, rear-wheel drive vehicles and on propeller shafts found in rear-wheel drive, all-wheel drive and four-wheel drive vehicles. The constant velocity joints are generally lubricated and sealed by a sealing boot. The constant velocity joints are sealed in order to retain grease inside the joint and keep contaminates, such as dirt and water, out of the joint. To achieve this protection a constant velocity joint is usually enclosed at the open end of the outer race by a sealing boot made of a rubber, thermoplastic or silicone type material. The opposite end of the outer race generally is enclosed by a dome or cap, commonly known as a grease cap. A monoblock or integral stem and race design style joint is sealed by the internal geometry of the outer race. This sealing and protection of the constant velocity joint prevents contamination of the inner chamber of the constant velocity joint that may cause internal damage to the joint.
A main function of a constant velocity joint is the transmission of rotational torque at a constant velocity. Traditional constant velocity joint assemblies include a variety of bolted joint designs to assemble the joint to a propeller shaft or half shaft within an automotive vehicle. Other assemblies are welded or use other chemical or mechanical bonding methods to secure a constant velocity joint to a tube or other propeller shaft component.
Many of these traditional constant velocity joints use a plug that is pressed into place within the constant velocity joint outer race or tube. These traditional plugs are capable of being dislodged allowing disassembly and loss of sealing function of the constant velocity joint under certain pre-defined parameters. Furthermore, the integrity of sealing components and retaining rings used to create positive stops for varying types of CV joints, including fixed joints, plunging joints, or crashworthy joints, and to seal contaminates from entering the internal chamber of a constant velocity joint may decay with time and the harsh environments found in constant velocity joints. Therefore, costly repairs may be necessary to replace seals and/or to repair seals in the constant velocity joint environment. Furthermore, many of the plunging constant velocity joints typically have a monoblock design, which requires a heavier constant velocity joint thus increasing weight for the automotive manufacturing and requisite gas mileage for the vehicles.
Therefore, there is a need in the art for a constant velocity joint that has a plug installed into an outer race, tube or other component that will be used as a seal and as a positive stop for any known type of constant velocity joint. There also is a need in the art for a lighter weight constant velocity joint that is easier to manufacture and more cost effective than traditional constant velocity joints.